The best SIM-only deals in 2024, based on the results our mobile network customer survey and our full reviews

The best SIM-only deals can be tricky to find: mobile networks like to bombard potential customers, or returning ones, with attention-grabbing discounts and freebies. Plus, how do you know youll be getting good value for money? Thats where I come in.

Below, Ive used my years of experience as a deals-hunter to collect all of the best SIM offers in one place. Theres something for every budget and type of user here from TikTok addicts and speed demons to those who just need a fuss-free plan that wont cost the earth.

If youre not sure where to start, scroll down to my buying guide at the bottom of the page, where Ive put together a list of questions you should ask yourself before taking the plunge. Youll also find more details on how I hunt down the best deals further down the page.

Best SIM-only deals: At a glance

The best SIM-only deals you can sign up for in 2024

1. Voxi: The best SIM-only deal

Price: £15/mth | View deal at Voxi

Pros

Voxi is a mobile virtual network operator (MVNO) that uses Vodafones network and its fair to say Im a big fan. Not only did we give it five stars out of five and a rare Best Buy award in our full Voxi review, but the thousands of respondents to our latest Expert Reviews Mobile Network Awards survey crowned it as the overall winner.Our reviewer Stuart Andrews particularly liked Voxis head-turning deals such as this one unlimited extras, commitment-free plans, rock-solid reliability and excellent performance.

Ive picked out one deal in particular that you should consider: 105GB of 5G data (a whopping 70GB up from the normal allowance of 35GB) for just £15/mth on a one-month plan that you can cancel at any time. Heres the clincher, though: youll also get unlimited use of social media and music apps, including Instagram, Spotify, Facebook, Twitter/X, Apple Music, Snapchat and more.

Cons

The only gnats in the ointment were the fact that it’s slightly pricier than options further down this list and it charges for roaming abroad, although it’s hardly alone in that respect.

Read our full Voxi review

2. Smarty: The best SIM-only deal with unlimited data

Price: £20/mth | View deal at Smarty

Pros

Weve been big admirers of Smarty for a few years now and so have the respondents to our annual Mobile Network Awards survey. In our most recent Smarty review, we awarded the Three-powered MVNO five stars out of five and an Expert Reviews Recommended gong, which was backed up by its second-place finish in the awards.

Its not hard to see why we like Smarty so much: it serves up great-value deals with lots of data, its 5G performance is up there with the best, and its free EU roaming allowance of 30GB is one of the most generous around.

So, if like me you want the peace of mind that comes with an unlimited deal, this is simply the best around: bottomless 5G data for £20/mth on a rolling, 30-day plan that you can cancel whenever you like.

Cons

Smarty’s customer-satisfaction scores were slightly down from last year and the company doesn’t offer eSIMs, which is a deal-breaker for those with phones without SIM trays.

Read our full Smarty review

3. Tesco Mobile: The best SIM-only deal for customer service

Price: £15/mth (£13/mth with Tesco Clubcard) | View deal at Tesco Mobile

Pros

Tesco Mobile is an MVNO running on O2s network and has truly embraced the parent companys motto of every little helps especially when it comes to customer service. In our most recent, full-length Tesco Mobile review, we garlanded it with four stars out of five and an Recommended award after it took home the Best Customer Service silverware at our yearly Expert Reviews Mobile Network Awards.

In particular, we highlighted Tesco Mobiles free roaming in the EU (a real rarity nowadays), solid reliability results, superb customer service and tasty discounts for Tesco Clubcard holders in our review.

The deal Ive picked out here gets you 60GB of 5G-compatible data for £15/mth on a two-year contract, but that will fall to £13/mth if youve signed up for a Tesco Clubcard. Moreover, Clubcard owners will be immune to any mid-contract price increases for the full 24 months, while those without one will be subject to price hikes every April of the Consumer Price Index (CPI) rate of inflation plus an additional 3.9%. Luckily, signing up for a Clubcard is free.

Cons

The main question marks were over performance, with both 4G and 5G speeds not matching those of its competitors. Meanwhile, 5G coverage is still patchy, but its steadily improving.

Read our full Tesco Mobile review

4. Lebara: The best SIM-only deal for calling abroad

Price: £15/mth | View deal at Lebara

Pros

It might not have the name recognition of other networks on this list, but Lebara has been going from strength to strength over the past few years. An MVNO running on Vodafones network, its tailor-made for those wanting to stay in touch with friends and family abroad, while being able to use up all of their data allowance in the EU and India (or up to 30GB if you’re on an unlimited plan). In our latest Lebara review, we gave it four stars out of five and an Expert Reviews Recommended award.

We singled out its bargain 30-day plans of which this is a prime example as well as its bundling of hundreds of international minutes and free roaming for praise in our review. We concluded overall that as a cheap and cheerful mobile network, Lebara has a lot to give.

This is my pick of its SIM-only deals at the moment: 40GB of 5G data for £15/mth on a rolling, 30-day plan that you can change or cancel whenever you like plus 500 international minutes to 42 countries, including the EU, India, Australia, Canada, New Zealand, the US and Ukraine.

Cons

We did have questions about its lacklustre customer service scores in the Expert Reviews Mobile Network Awards survey and inconsistent performance.

Read our full Lebara review

Where are the other mobile networks?

You might have noticed a few glaring omissions, such as Vodafone, from my list. Simply put, this is because Im not happy to recommend these mobile networks based on their most recent in-depth reviews on our site and the results of our annual Best Mobile Network Awards survey. Below, youll find a quick rundown of why they didnt make the cut, along with links to our reviews

1. Three: Fast 5G, but poor customer service

Appropriately, we gave Three three stars out of our five in our latest review. Despite being impressed by both its 5G speeds and coverage, we couldnt look past its mediocre customer service in our Best Mobile Network Awards. As we explained, just 19% of Three users told us they were very satisfied with their customer service, with only 37% fairly satisfied.

Read our full Three review

2. Vodafone: Nice extras, but so-so performance

It was a similar story with Vodafone, which is apt given that theres a plan to merge it with Three in the future. We awarded it three stars out of five, praising its feature-packed bundles and flexible phone deals while drawing attention to its middle-of-the-road performance and disappointing customer satisfaction scores.

Read our full Vodafone review

3. O2: Doesnt justify the high price

There are a lot of positives about O2: you can tailor contracts to your specific needs, there are plenty of handy extras and you get free EU roaming up to 25GB. However, all of that is undermined by the above-average prices, the poor customer service results and the fact that you can get faster speeds elsewhere. This led to a verdict of three stars out of five in our review.

Read our full O2 review

How does Expert Reviews find the best SIM-only deals for you?

As deals editor at Expert Reviews, theres nothing I like more than digging out a SIM-only offer that will save you money without any compromises. Below, Ive briefly outlined the method I use, but Ive also written about it in more detail at this dedicated page.

Have we given the mobile network a good review?

Like a certain wood-stain brand, Expert Reviews does exactly what it says on the tin. We gather together experts in their fields to produce in-depth reviews and mobile networks are no exception. That means every deal you see above will be based on the write-up weve given it in the past, as well as the results of our annual Mobile Network Awards customer survey. If a mobile network isnt up to snuff or we havent reviewed it, I wont recommend one of its offers.

Is there something for everyone?

At Expert Reviews, we realise that one persons bargain is another persons splurge, particularly in these financially tricky times. Consequently, Ill always make sure that theres a range of different deals for every budget in the roundup as well as covering the other options from the same provider in a table beneath the mini-reviews.

Are there any hidden catches?

Although mobile networks are meant to flag any hidden fees or rises as obviously as possible, it can still be easy to stumble into a trap. Thats especially true for the new mid-contract price hikes, which involve certain networks increasing prices by a set amount every year (usually the Consumer Price Index rate of inflation plus an extra 3.9%).

To put it mildly, these arent great and, wherever possible, Ill avoid recommending any deal that will become more expensive as time passes. However, if one does make the list, Ill always be transparent in the mini-review and justify its inclusion.

How to pick the best SIM-only deal for you

Not sure where to begin with my list of recommended SIM-only deals above? Ive put together a quick, jargon-free, checklist below that will answer all of the major questions.

What is a mobile virtual mobile operator (MVNO)?

Mobile virtual mobile operators (or MVNOs, to avoid the mouthful) are simply smaller networks that piggyback on one of the four major ones: EE, Three, Vodafone and O2.

For instance, Voxi uses Vodafones network, while Smarty and iD Mobile make use of Threes. MVNOs tend to be much better value than one of the giants, offering shorter-term plans that you can escape at any time.

READ NEXT: How to avoid price hikes with an MVNO

How much data do you need?

This depends on how much you use your phone when youre not connected to Wi-Fi. If you only do a spot of browsing and listening to music on your commute, 20GB to 50GB should be enough.

If, on the other hand, you like to devour Netflix, play games and use your phone as a personal hotspot for your laptop, youll need a big data plan such as 100GB or unlimited. Luckily, these are now affordable and often represent the best value.

At the other end of the scale, Id recommend steering clear of any data plan under 10GB unless youre sure it will be enough.

How long should the contract be?

Most SIM-only contracts generally last 12 months, but some networks are now offering compelling deals that sign you up for 18 months or two years. You can save some money by going for a longer-term plan, but you should always double-check if there are any mid-contract price hikes as, unfortunately, these are increasingly common.

You can also pick up rolling, one-month plans from the likes of Voxi and Smarty, which are both excellent mobile networks at the top of my list. These allow you to wriggle out whenever you like and jump to a better deal.

What speeds can you get?

Huge swathes of the UK can now get faster 5G speeds, but there are pockets where 4G is still the speediest option. To find out what you can get, you can either select one of the deals above and use the mobile networks own coverage checker or use Ofcoms tool for a general overview.

How much roaming is included?

Sadly, the days of being able to use all of your call, text and data allowance in the EU are gone. Instead, some mobile networks charge a daily fee to roam in Europe, while others let you roam for free up to a daily cap.

If youre heading further afield, expect to pay a lot more, although, as we explain in our roundup of the best roaming SIM-only deals, there are exceptions.

Written by

Max Figgett

Now deals editor at Expert Reviews, Max first joined the website in 2016 and has worked for numerous tech-focused publications over the past 13 years – including PC Pro, The Big Tech Question, Alphr and Wonderpedia – as well as the Daily Mirror, Total TV Guide, TV Choice, Take a Break, the Falmouth Packet and Welt der Wunder in Germany, among others. He’s sifted through thousands of deals on everything from broadband contracts to toothbrushes in his career so he knows what separates a great offer from a bad one.

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